Why can soap clean my hands off oily stuff like grease when soaps themselves are made largely of fat and oil?
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The actual soap molecule is a molecule that can disolve in both water and oil allowing them to mix (so making it easier to clean oily stuff off of your hands). Everything else in the soap is an addition to kill bacteria/ smell nice etc.
Soap molecules [create a chemical bridge/bond](https://kidsclinic.sg/wp-content/uploads/2020/04/how-soap-works.jpg) between fats/oils and water. One Hydrophyllic end is water soluable and the other hydrophobic one is fats/oils soluable, so the soap allows the oils which contain dirt & bacteria to be mixed with and rinsed off with water. This is the same way soap will kill some bacteria and viruses, one end mixes with the lipids (fats) that make up their body, breaks it up and thereby kills the bacteria or virus.
Soaps aren’t fats or oils. They’re the product of *reacting* fats with alkaline substances, traditionally usually lye (sodium hydroxide).
That reaction produces a molecule with two ‘sides’. The original fat on one side repels water and attracts fats, and the extra base attached to the molecule on the other side attracts water. The combination means that soaps can help fats dissolve in water, by bonding to both the fats and the water.
The main chemical in soap has ony end that can stick to water and the other end that can stick to oil. So it allows you to use water to remove oily stuff.
Coincidence, brand new video from Action Lab, “This Device Can Actually Make Oil and Water Mix!.” Spoiler!!!: the true answer is a vacuum pump. https://youtu.be/YJeWklggSpY
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